Hello @krzysiek.cris 

Do you have any of this in your fusebox, livingroom or somewhere else?

You could als find just a telephone cable. If you really can't find anything than a moderator could send a technician one your subscription has started.

In livingroom i have only tv socket and in fuse box I found cable similar to phone but somebody cut it off.

@krzysiek.cris 

What you could do is ask neighbours where their ISRA is located, it should be the same place in your house I guess.

Hi @krzysiek.cris, when an ISRA is cut-off, the grid operator (network administrator) has to repair the ISRA. However, I surmise that this is a so called “extended ISRA”. I think Waqqas’ advice to ask the neighbors where their main ISRA is located, is the best tip. Sometimes the installation points are located in the living room, or outside. 

If the main ISRA turns out to be the cut-off one, you can request a mechanic to come and take a look and label the ISRA. Once that has been done, you can ask the grid operator to repair the ISRA. Oftentimes repair costs are reimbursed by the operator, but that all depends on whether the ISRA has been cut-off on purpose or by accident. It's too early to tell, just based on pictures, but it looks like the wire has been cut with a specific purpose.